Art of preparing pitches



Patented Jan. 11,1921.

UNITED STATES PATENT OFFICE.

FRANCIS M. ROGERS AND OSCAR E. BRANSKY, OF WHITING, INDIANA, ASSIGNORS TO STANDARD OIL COMPANY, 01! WHITING,'INDIA NA, A CORPORATION OF IN- DIANA.

ART OF PREPARING BITCHES.

No Drawing.

This invention relates to methods for the production of binder; pitches suitable for use in saturating felts, briquetting coal, and the like and will be fully understood from the 5 following specification. i

In carrying out the present mventlon, use is made of the material commonly designated as acid coke, which makes up the intermediate layer of the sludge obtained by the treatment of parafiin distillate with strong sulfuric acid, for example, 66 B. acid after dilution andstratification. Upon Stratification, such sludges form three layers, a lower dilute sulfuric acid layer, an upper o1ly layer, and an intermediate or acid coke layer, which, upon cooling, becomes substantially solid. This material, up to the present time,

has found substantially no commercial use except as fuel.

In accordance with the present invention, a binder pitch, suitable for use in briquetting, saturating, macadamizing, etc., is produced by incorporating acid coke 1n sultable proportions in relatively heavy hydrocarbon oils of relatively high viscosity, say from 3 Engler upward (212 It is preferred that the oils employed be of greater density than water, such as, for example, the pressure tar or residuum from the Burton pressure still, reduced to the viscosity above set forth. For example, pressure tar reduced to a viscosity of 6 Engler at 212 F. has been found satisfactory for use in connection with the present invention.

The oil is heated to a temperature of above 160 F. and preferably about 200 F. A suitable proportion of acid coke, thoroughly washed with water, say from 15 to- 15 per cent, is then admixed therewith. The proportions used vary with the desired characteristics of' the final product; for example, for theproduction of a pitch suitable for use as a binder for briquets 25 per cent of acid coke, ma be employed. The mixture is blown with air at a temperature of 200 to 210 F. until the Water is substantially completely removed therefrom. It is then gradually heated up (with introduction of steam Application filed January 19, 1923; Serial No. 613,782.

at least after the temperature of 300 F. has been reached), the heating of the mixture being carried to about 600 F. or until the mixture has a melting point, in the case of a briquetting pitch, of 145 to 150 F. The melting point desired in the final product .will vary with the precise nature of the roduct desired, and in an case, the heating terminate when a pitcii of the desired melting point has been obtained.

We claim:

1. The method of producing a binder pitch which consists in introducing acid coke into a heavy hydrocarbon oil and reducing the mixture by fire and steam at a temperature not above about 600 F., to the desired meltingpoint.

2. The method of producing a binder pitch which consists in introducing from 15 to 45 per cent of acid coke into a hydrocarbon oil of a viscosity of at least 3 Engler, at 212 F., and heating the mixture in the presence of steam to a temperature not above about 600 F., toproduce a pitch of the desired melting point.

3. The method of producing a binder pitch which consists in introducing from 15 to 45 per cent of acid coke into a pressure tar residuum and heating the mixture in the presence of steam toa temperature not above about 600 F., to produce apitch of the desired melting point.

4. The method of producing a briquetting pitch which consists in admixing 20 per cent of acid coke with a pressure tar residmim having a viscosity of 6 Engler at 212 F., and heating the mixturein the presence of steamto about 600 F.

5. The method of producing a binder pitch which consists in heating a heavy hydrocarbon oil to about 200 F., introducing acid coke thereinto, and subsequently heating the mixture in the presence of steam to a temperature not above about 600 F., to produce a pitch having the desired melting point.

FRANCIS M. ROGERS. OSCAR E. BRANSKY. 

